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OB99W

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Everything posted by OB99W

  1. I'll respond to your last question first. I do believe you have a point; Subaru doesn't step up to the plate on some issues; just ask people who've had to pay out-of-pocket for head gasket repairs. As to whether you have a winable case (and no, I'm not a lawyer either), I suspect that you may have some difficulties. You have yourself admitted that "Most likely they did not even know about their VC unit's limits and performance."; that in itself could eliminate any claim that not informing you would be considered willfully negligent. Having said the above, some things in the 1999 Owner's Manual certainly could have lead you to assume that tire circumference differences don't matter. On pages 10-46 and 10-47, I found the following: ------------------------- When rotating tires, replace any unevenly worn or damaged tire. After rotating the tires, adjust tire pressure and be sure to check wheel nut tightness. A tire should be replaced when the tread wear indicator appears as a solid band across the tread. The indicators appear when the remaining tread has been worn to 0.063 in (1.6 mm) or less. ------------------------- Note that it says to replace "any ... tire" and "a tire", not all tires at the same time. You could easily wind up with one new tire and three worn ones by following the manual's advice, obviously exceeding the "requirement" of having less than 1/4" difference in circumference between the most- and least-worn tire. If Subaru didn't know of the importance of minimizing the tire size difference when the '99 manual was printed (which is questionable), they certainly have known it since then. Given the importance of the issue, one could argue that an informative letter should have gone out to all owner's of the AWD vehicles. It all comes down to whether this is worth pursuing. I tried a legal remedy for a particular matter; it took years to resolve, with the outcome being only the lawyers were the winners. My read of your situation: I sympathize, but it's small potatoes; perhaps try to get SoA to compromise on repair costs, but otherwise let it go and move on.
  2. Sure . I did the calculations a while back; here's what I previously posted: ------------------- Based on the full capacity of the 4EAT and typical drainage from the pan by just removing the plug (with the car level), I roughly calculated the percentage of old ATF replaced with new by multiple drain/fills. The following is in the form #-of-changes -- %-fresh-ATF: 1 -- 40% 2 -- 64% 3 -- 78% 4 -- 87% 5 -- 92% ------------------- Naturally, if you wait significant time (months or more) between the drain/fills, the "fresh" ATF won't all be as fresh as if you do the changes in rapid succession.
  3. Unfortunately, on an engine with 163k miles (yes, even an EJ, and even if the oil has been changed on a regular basis ), there's a certain amount of "sludge"/"varnish"/"whatever" that builds up in places. Sometimes it's in places that cause problems; sometimes it's filling gaps, and removing it causes problems. Piston slap on an EJ usually shows up mainly on a cold engine, and gradually abates when things expand as the engine warms. What viscosity were you running when the noise was apparent? Did the noise show up mainly with a cold engine, or even after it was thoroughly warmed? Did the 15W40 completely quiet what you're hearing when the engine is cold, and when warm as well? Although written concerning the 2.5, this is interesting: http://endwrench.com/images/pdfs/KnockingInfo.pdf
  4. As I've been saying, and you've been ignoring, tensile forces can cause fatigue which leads to failure. The final, complete fracture might well occur at any point, including a time of compression. That doesn't mean tensile forces didn't lead to or compound the problem. Certainly those are two possible causes, but not the only ones. Please do the math, and let us know the results. Once you do, and think you have "proof" that the forces couldn't be sufficient to be a problem, I'll have further comment. You may be surprised at what's involved that may not be immediately obvious. Oh, and to avoid confusion, I'm OB99W, not obw99.
  5. Actually, a decent tire calculator is probably all you need. I like this one: http://www.net-comber.com/tirecalc.html . The 2002 WRX came with 205/55R16 tires; they'd be a lot closer in size to 195/70R14 than 215/60R16 would. The additional 0.4" width would of course reduce clearance by only 0.2" at each sidewall, so it's unlikely (unless you have bent sheetmetal or suspension problems) that it would create a problem.
  6. No, I'm saying that it can contribute to fatigue that may lead to eventual failure. That's theoretically true, but mostly borne out only in lab testing of samples that have no irregular surfaces. In the real world, metals often have rough finishes and develop surface fissures/cracks as they are manufactured/used/abused. Those irregularities tend to close up during compression and so aren't much of a factor for strength in that mode; however, under tension they can open and grow, possibly becoming severe enough to cause complete fracture. So barring 1) and 2) (and ignoring bearing surfaces), are you saying that a rod with 279k miles of use on it is in the same condition as when it was manufactured? Are you also saying that mountain driving with high-RPM engine braking doesn't stress engine components such as connecting rods more than level driving, or perhaps that it only stresses them in compression but not tension? As to cars that are modified for racing, a typical approach is to use parts such as connecting rods that are carefully radiused and polished in order to minimize the development of stress cracks that lead to failure.
  7. The key to maintaining control is to have minimal difference in the tangential speed of the tires relative to the road surface. Anything done to induce a significant change can cause loss of traction. The tires and road surface don't care whether a speed difference is induced by pedal braking or engine braking. Pedal braking can certainly induce the speed difference, but if a loss of traction happens, getting off the pedal normally results in the wheels coming back up to speed in a reasonable time (except, perhaps, on glare ice). Unfortunately, if downshifting results in loss of traction, getting the drive train speed back up so that the tires and road are "in sync" again requires either a lot more time to accelerate the drive train against the engine braking, upshifting, or actually getting on the gas (totally non-intuitive for most people, particularly if they're going downhill). Sure, downshifting with caution, not picking too low a gear, and the engine braking developed can slow the car without too much loss of traction. Downshifting unnecessarily on a slick surface can lead to more likelihood of traction loss, AWD or not, since the wheel torque is higher the lower the gear. Pedal braking (like many other things in life ) can be done to excess, especially by inexperienced drivers. Learning how to drive under all kinds of weather/road conditions is always a good idea.
  8. Who said anything about spinning a bearing? Con-rod failure is often due to stress fractures, and the rod breaks at the beam near either the big or small end. An engine with 279k miles on it may have had lots of stress on the rods already. Metals, like many materials, are typically much stronger in compression than in tension. There are reasons why mountain driving sometimes leads to a rod through the block; the additional stress caused by uphill power requirements isn't the only one. Conditions under high revs with closed throttle are not the same as under identical high revs but with the throttle open. The increased tension in the rod isn't great, but it isn't insignificant either. Most people think that the reason engine braking works is due to losses during the compression stroke; it seems obvious that forcing those air molecules together would expend lots of energy, but you get most of it back when the "air spring" pushes the piston back down again as soon as TDC (top dead center) is passed and the air reexpands (darn thermodynamics ). Actually, the energy loss (and therefore braking effect) is mostly due to the effort required on the intake stroke, pulling a vacuum against the closed throttle. Whatever energy that is, the connecting rods see the increased tension caused by it. Back to the original focus of the thread -- proper pedal braking in conjunction with a suitable gear selection for engine braking is the right approach.
  9. Perhaps if you could be a bit more descriptive, someone might be able to offer some help. Where does the "hum" seem to be coming from? Why do you think it's electrical in nature? Since it's evident with the key removed, you might open the hood and see if the source is in the engine compartment. Move around the car and try to localize the sound, then get back to us.
  10. Besides bolt pattern & circle and wheel offset, the centerbore needs to be correct as well.
  11. With careful diagnosis, it's usually possible to determine whether it's the cat or O2 sensor alone causing the code, or a bad O2 sensor that also killed the cat. If both have high mileage, it could certainly be either or both. In a shop, it doesn't "pay" to hang a lot of parts if replacing one will clear the code. However, if an owner can provide the labor, changing an oxygen sensor that has a lot of miles on it will probably not be a waste of money; if it doesn't cure the P0420, it might just provide better gas mileage, or help keep a new cat (if needed) healthy. How long is "for good", and are you also replacing oxygen sensors or at least testing them for proper response? Hanging a new cat might get rid of the code, but if the sensor is marginal, the new cat might not have "nine lives".
  12. Nipper, based on your understanding of thermodynamics, I don't understand how you could say the following about friction braking in your post #3: In a properly designed and maintained automotive service brake system, there should be no difference in the heat buildup whether the brakes are applied constantly (controlled braking) or stabbed/snubbed. Snub braking is a technique taught to truckers driving big rigs; it's necessary because air brakes found on some tractors/trailers don't all actuate under light braking (low air pressure), and that can cause excessive heating in the trailer brakes while leaving the tractor's relatively cool. By braking more heavily, there's a much better chance that all the brakes will actuate (due to higher air pressure), and the heat will be more evenly distributed. Snub braking a car isn't wrong, especially if the road is dry and free of loose material, but under slippery conditions it can lead to a slide. Controlled braking is less likely to cause that. Of course, if a car is in a slide, pumping the brakes can help in regaining steering control while still slowing the car. (In case anyone is wondering why I keep mentioning the possibility of a slide, it's due to "I just started a new job at a ski/golf resort" in the original post. It may not be ski season yet, but developing good habits before then is better than trying to break bads ones when it counts.) Assuming good initial design, brake balance can be retained by proper maintenance. That means pads/shoes have to be decent, the rotors/drums free of significant rust and not cut beyond spec, nothing is hanging up due to corrosion or lack of lubrication, etc. Get the brakes in shape (if they're not at this time), then combine correct gear selection with prudent brake pedal usage, and there shouldn't be a problem descending mile-long 15% grades.
  13. The "addage" is only dangerous if friction brakes are used to the exclusion of engine braking. Nipper, since it seems your statement was in response to mine, let me make it clear that I'm not suggesting that friction brakes be used as the sole means of slowing a vehicle on a 15%/one-mile-long grade. This all depends upon the grade/length, and quality/condition of the brakes. That's why I suggested that untrustworthy brakes be worked on until they're up to proper performance. Using the service brakes in conjunction with engine braking is the right thing to do, but in the correct proportion. Choosing particularly low gearing that results in high engine revs, while not resorting to friction braking until the last moment, isn't the best approach. I'm again going to assume that you're responding to my previous statement. I didn't say that this behavior would necessarily result in a "blown" engine. However, what happens under engine braking is that the forces on certain parts are not the same as those under cylinder firing. In particular, the connecting rods see high tensile forces during part of the stroke that they aren't "normally" asked to sustain. Know anyone who's had a rod fail while driving in a mountainous area? One more aspect of engine braking versus friction braking has to do with driving under slippery conditions. If you begin sliding due to excessive friction braking, lifting your foot off the pedal (an almost "automatic" response for most experienced drivers) will usually help regain control of the car. If instead you've downshifted, and start sliding due to excessive engine braking, if you don't react fast enough and quickly upshift (not an "automatic" response for most of us) you may not recover from the slide. I hope the above is food for thought.
  14. The engine will probably take that kind of treatment, for a while, anyway, but especially with the mileage you have on it that's probably not the best thing to be doing. My personal philosophy is that brake linings are a lot cheaper, and easier to replace, than engines. Unless you don't trust your brakes (in which case, they should be worked on until they can be trusted not to fade, etc., on a long/steep descent), why have the engine rev that high on a regular basis? By the way, what does the speedo read just before you're hitting the brakes?
  15. Excuse me, but what is that supposed to accomplish? See this article for a bit more insight: http://www.motor.com/MAGAZINE/Pdf/102006_09.pdf
  16. Yeah, my own OB holds to about 23 MPH, but the "official" speed (as found in the owner's manual) is 25.
  17. Much of it is based on past experience with particular systems or materials. If something is so "new" that there isn't much previous data, one technique that's used is "accelerated life testing"; do a Google search on that to learn more.
  18. Yes, a tube or other guide can help both with centering and being on-axis, which is just as important. I've used coupling nuts (see http://www.chicagohardware.com/nuts.htm if anyone doesn't know that term), pieces of water line, brake line, etc., sometimes alone but often nested in each other. A trip to hardware and plumbing supply places can help your imagination. (By the way, the coupling nuts can be useful both when the break is recessed and when the remnant projects beyond the surface. For the recessed situation, obviously the hex has to fit inside the threaded hole, so it can be a little tricky to find the correct size. For the times when a portion is above the surface, matching threads can help.) Should it have to go that far, there are a few things to be sure of when tapping: 1) Drill the correct diameter hole for the particular tap; too large, and the threads won't be full-depth and will be weak -- too small, and the tap may jam 2) Use appropriate lubricant; don't, and the threads will suffer and the tap may jam 3) Start the tap on-axis; if it's cocked, it will likely jam. 4) Back the tap out frequently and clear chips; don't, and the threads can become ragged or the tap may jam 5) Take your time and trust your instincts; if it seems that too much effort is needed, stop and determine why, or the tap may jam 6) I don't mean to alarm about the jamming , but ignoring things like the above are typical ways that some beginners have trouble You're welcome. I already wished you luck back in post #24 of this thread, but I'll gladly wish you some more of the best kind. hmmm Breaking that bolt is certainly not a common problem. It looks like my broken bolt is longer (judging from the pic). Just to confirm, my threads start 1-3/8" down from the head. If this is the same as yours, they may have used an EJ25 bolt in my EJ22 engine. Not sure if this means my bolt bottomed out and the remnent will be highly torqued! If so, I may not be able to back it out. Skip, thanks for the "heads up". Jim, I certainly hope that someone didn't previously use a too-long bolt, and this all works out for you.
  19. Based on the diagram and the list of non-functional items, I'd start by looking at fuse number 15.
  20. Obviously, fuel delivery problems could be the cause of the misfire, as can problems at the particular cylinder, but ignition faults are often the cause and therefore the first thing to check. Since the part of the coil pack that fires cylinder #3 also fires #4, but you aren't reporting P0304, it's likely that the coil is okay. Since Subarus are fussy about ignition wires, we usually suggest that only OEM ones be used. You could check if there's any high-voltage leakage; spray down the ignition wires with a water mist, and see if the misfire becomes more obvious. If you do this when it's dark, you can look for sparks; any you see indicate a problem, since a good ignition system can withstand the water. Also, make sure that the connections at the plugs and coil are fully seated and making good contact. Or, just change the plug wires to originals. Of course, just because the plugs were changed "last summer" doesn't mean that they're out of condideration. However, if the mileage has been fairly low since then, they're probably okay; I'd concentrate on the plug wires first.
  21. I agree, even if the bolt remnant proves somewhat reluctant to come out, it should be doable. Lubrication and slow, careful work are the keys. Mostly, if anything seems to be seizing during the extraction, it's time to take a break and rethink the situation.
  22. The problem is, apparently the remnant is recessed by 1/4" or so into the crank. See my previous posts concerning bolt deformation once elastic limit is exceeded and the bolt goes through the yield zone. Yes, breaking off any hardened tool will make things worse. I'd still like to know what grade/class this particular bolt claims to be.
  23. If the "long bolt" is right-hand threaded, I suspect if the bolt remnant is free to turn it will be driven further in by this approach, until there's bottoming, and then things will jam; if the remnant is stuck, the additional bolt will eventually bottom, then jam. If a left-hand threaded bolt is used, it may help turn the remnant out. However, if the remnant is stuck, the additional bolt could possibly thread until it bottomed, and perhaps jam. But there's no guarantee that the remnant isn't seized. As I mentioned before, when a bolt snaps, it's exceeded its elastic limit. That means it's stretched (yield zone) and won't return to original dimensions, particularly in the area of the break. Depending on tolerances, there could now be an "interference fit" between the threads of the bolt remnant and the crank's threading. Gary, I liked your previous idea of drilling, tapping, and using loctite on an unhardened bolt; if it breaks, at least there's just a soft piece of metal, no worse than the original remnant, to deal with (as long as the tap doesn't get broken; see below). I don't have one at hand either, but I believe the crank bolt diameter is 14mm, so 3/16" would be "small" compared to that, but probably not too fragile. Nobody is going to like me for this, but... taps have a taper, and sometimes jam and break, and they're also hardened. If the tap is being used to allow insertion of a bolt that will be used as removal tool, the tap needs to be properly lubricated, and backed out frequently to remove chips, or it may jam. If the tap is being used as a removal tool itself, then jamming might be "okay", but you run the risk of breakage. Yeah, I'm a real "killjoy".
  24. Small bits are usually easier to start a hole with, but they're also easy to break if you apply pressure off-axis. Since they're made of hardened steel, you can wind up with a problem similar to a broken-off "easy out". Starting with a small bit is fine, just not "too" small; if you can deflect it with a little side pressure, there's a good chance of breaking it while drilling (using a hand-held drill in an awkward position, anyway).
  25. If the problem is intermittent and the electrical load isn't high, the battery may still get a sufficient charge. As already mentioned, a dying alternator can cause the symptom you're experiencing. However, so can loose/poor connections, and they don't have to be grounds. If you can attach a voltmeter that can be read (safely!) while driving, see what it says when the problem occurs.
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